MAP22: Limbo (Console Doom)

MAP22: Limbo is the twenty-second and penultimate level of most console versions of Doom, based on the original E3M7: Limbo with modifications made to adapt to the consoles' memory and ROM size limitations. It was converted by American McGee and originally designed by Sandy Petersen. The map first appeared on the Atari Jaguar, and was later ported to the 3DO, Game Boy Advance, Sony PlayStation, and Sega Saturn consoles.

Essentials
Start by heading forward to a large round room filled with lava. Follow the semi-circular platform to the left, go through the doorway and then turn left to a gray octagonal structure. Turn left and head forward to a high-ceilinged area with metal pillars. In the corner ahead is the blue skull key on a platform surrounded by lava. The bridges next to the platform drop away when you take the key, but this should not be an issue.

Backtrack to the circular room and follow the semi-circular platform round to the east doorway. Through here are two blue doors - go through the north door, drop into the lava pit behind it and climb the stairs. Keep going forward to find a hole in the floor, leading to a maze of lava-filled passages. Drop into the hole and go forward to an island with radiation shielding suits. Take one and go through the west exit, then go forward to a second island with more radiation suits. Go through the west or north exits from here and keep heading west. If you see a teleporter, do not use it yet - go south and west to find a platform with the red skull key, guarded by a shotgun guy. After taking the key, press the gargoyle switch on the south wall then press the skull switch directly behind it. Return to the teleporter you passed earlier and step into it.

You will return to the area where you found the blue key. Backtrack to the large circular room and head north across the lava to the north doorway. In the next area, turn left and head towards the hexagonal brick structure in front of you - inside is a teleporter that leads to a platform in the exit area. Press the switch on the west wall, then drop into the lava and head east up some steps; a bridge has raised here so you can reach the yellow skull key. Step into the nearby teleporter to return to the previous area. When you step off the teleporter, turn right and right again; you will see a platform in front of you with another radiation suit and medikits, should you need them.

Return to the area where you found the blue key and head southwest, to a lava pool in the south-west corner of the level. Enter this pool and go north to find another brick structure with a teleporter; step into it and press the switch in the room you arrive in, then backtrack through the teleporter and return to the circular room. Enter the teleporter inside the brick structure in the center of this room; in the small room you arrive in, cross the bridge, open the yellow door and press the switch behind it. This raises a bridge to the exit door.

Head back through the teleporter to the circular room and head through the west doorway. Turn right here and follow the passage to yet another lava pool with a brick structure. Enter the teleporter here, open the yellow door ahead of you and you will see the exit door across the bridge you just raised. Cross the bridge, open the exit door and step on the teleporter pad to finish the level.

Other points of interest
At the start of the level, turn around to see a wooden door. Open it to reveal an alcove containing a backpack, as well as two cacodemons on Hurt Me Plenty or Ultra Violence skill levels. The alcove will also open when you enter the circular room north of the start point.

In the south-western corner of the map is a lava pool with a switch in its south-eastern corner. Pressing this switch opens the gray octagonal structure in the area to the north. Inside the structure is a star with a soulsphere, a rocket launcher and a box of rockets on it. These items are guarded by two or four cacodemons depending on skill level.

Secrets

 * 1) South-east of the star chamber in the west of the map is a vaguely hexagonal green marble structure. Walk around the back of this structure and two of its walls will open, revealing a secret area that contains a megaarmor. (sector 130) It also contains a number of demons and lost souls.
 * 2) In the north-eastern corner of the map is a maze of lava-filled tunnels. From its start, head right, right, left, then right. You will arrive at a platform with a BFG9000. (sector 31) Watch out for the shotgun guy waiting in ambush.
 * 3) After pressing the switch next to the red skull key in the lava maze, return to the central area after taking one of the teleporters in the maze. Go through the southern of the two blue doors in the room to the east. In a nearby alcove is a switch; press it to lower a wall back outside. Press a second switch behind the newly lowered wall to raise a bridge to the teleporter in the south-eastern corner of this room. Go through that teleporter to be taken to a secret area with armor and a plasma gun. (sector 51)

Bugs
A set of 4 shotgun shells (thing 59) and an energy cell (thing 120) have no flags set for any of the difficulty classes, so they do not actually appear in the level.

Comparison of versions
Numerous changes exist in the level compared with its PC version:

Geometry simplification

 * The island in the middle of the large round chamber at the center of the map has six sides instead of nine.
 * All the teleport chambers in the level, which are opened with the red skull key, now have six sides instead of eight.
 * There is a step in front of the hole that leads to the blood-filled hallways in the north-east side of the map. Part of this step has been removed, reducing the number of lines.
 * Two of the walls in the room in the south-west corner of the map have been merged together.
 * Three of the walls in the chamber in the north-west corner of the map have been merged together.

Room design
Some rooms in the level were redesigned:
 * Blood pits throughout the level are changed to lava.
 * The staircases leading out of lava pits on the east side of the level have fewer steps.
 * The large round chamber at the center of the level is open to the sky, instead of having a ceiling.
 * The blood pools around the star on the west side of the map have been removed, while the star itself is now a lava pit and is not marked as secret. The sky is also visible above the star.
 * The teleporter in the lava pools north and south of the star chamber have been moved further from the walls, probably to accommodate the player's increased radius.
 * The lava pool in the south-west corner of the map has been reduced in size.
 * The lava-filled hallways in the north-east area of the map are wider due to the player's increased radius. A dead-end hallway connected to one of the islands has also been removed.

PlayStation
Some additional changes were made in the PlayStation port:
 * The bridge in the north-eastern room behind the blue door has been removed, along with the switch that raises it (normally located in an alcove on the south wall, west of the island holding the blue skull key). This has practically no effect on gameplay as the player can simply run through the pit and climb the stairs to get past this obstacle.

Music
The map uses the following music tracks:

Player spawns
This level contains four spawn points:
 * 1) facing north. (thing 134)
 * 2) facing north. (thing 135)
 * 3) facing north. (thing 136)
 * 4) facing north. (thing 137)

Things
This level contains the following numbers of things per skill level: